Manual implement of synthetic resin, such as forceps for medical use

Abstract: The implement comprises two members (2, 3) which intersect in an intermediate region and are arranged to rotate one relative to the other; of said members (2, 3), that portion (21, 31) which acts on objects is positioned at one of their ends, and that portion (22, 32) which is operated by the hand is positioned at the other end; the first member (2) passes through a through slot (4) provided within the thickness of the second member (3); said slot (4) defines within the member (3) two spaced-apart walls (33) which embrace the member (2); said slot (4) has a length such as to enable the two members (2, 3) to rotate relative to each other; a flexible strip (5) is provided joining together the two members (2, 3) to define the hinge constraint between the two members (2, 3); said two members (2, 3) and said strip (5) are formed in one piece from synthetic resin.

Description: This invention relates to a manual implement of synthetic resin, such as a forceps for medical use or a like object such as small scissors, comprising two members which mutually intersect in an intermediate region and rotate one relative to the other; of said members, that portion which acts on objects is positioned at one end and that portion which is operated by the hand is positioned at the other end. In FR-A-2024956, an implement according to the preamble of claim 1 is disclosed. The purpose of medical forceps is to clamp various objects, for example for squeezing flexible tubes in order to close their passage. Known medical forceps possess two separate members connected together by a metal rivet which defines a hinge pin. This results in various drawbacks. Firstly, the presence of the metal rivet is a hindrance to the recycling of a discarded forceps for recovering its synthetic resin. In addition, the clinching of the rivet can never be of a constant extent, with the result that the two members are sometimes pressed together too tightly or too loosely. The object of the present invention is to overcome these and other drawbacks. The present invention, as characterised in claim 1, provides an implement the construction of which is economical as it is formed by a single moulding operation, it therefore being unnecessary to assemble the two members together (they being formed already assembled). In addition to the preceding features, which are known from FR-A-2024956, the two members are properly guided because one passes through the other, one therefore acting as a guide for the other. They therefore flex to a lesser extent when subjected to force. In addition the implement according to the invention can be properly recycled as it is constructed completely of synthetic resin. The invention is described in detail hereinafter with the aid of the accompanying figures, which illustrate one embodiment thereof. Figure 1 is a view of a forceps for medical use according to the invention. Figure 2 is a section on the plane II-II of Figure 1. Figure 3 is a section on the plane III-III of Figure 1. Figure 4 shows the forceps of Figure 1 in position clamped on a tube. The implement of the invention consists of two members 2 and 3 which intersect in an intermediate region and are arranged to rotate one relative to the other. Each member 2, 3 has at one end a portion 21, 31 respectively by which it acts on objects 9 to clamp them (Figure 4). It also has, at its other end, a portion 22, 32 respectively for the operation of the hand. The portions 22 and 32 are for example in the form of eyelets, as in the case of usual scissors. A flexible strip 5 is provided between the portions 21 and 31 and the region of mutual intersection of the two members 2 and 3 to join the two members 2 and 3 together and define the hinge constraint between them. Within the thickness of the member 3 there is provided a through slot 4 through which the member 2 passes; the slot 4 has a length (in the direction of the longitudinal central line of the member 3) greater than the width of the member 2 in that region, to enable the two members 2 and 3 to rotate relative to each other. The slot 4 defines within the member 3 two spaced-apart thin walls 33 which embrace the other member 2 on the two sides. Specifically, the slot 4 has a narrower portion 4' of constant width, in that the distance between the inner surfaces of the walls 33 is constant at that point; said portion 4' is obtained by an inwardly projecting step 33' of triangular plan provided within the thickness of each wall 33 (Figure 2). The width of the slot portion 4' is substantially equal to the thickness of that portion 24 of the member 2 which moves within the slot 4. The portion 4' and the portion 24 are engaged with each other under conditions of sliding contact when the forceps is closed (Figure 4). Consequently the two members 2 and 3 are mutually constrained (in the direction of the axis of mutual rotation) in particular when they are in their closed position, this position being that in which most force is exerted on the implement. They are therefore mutually guided and (conveniently) have lesser possibility of bending in the plane within which they rotate. The other portion 4'' of the slot 4 is more displaced towards the strip 5 and has a width substantially greater than the thickness of the portion 24 of the member 2. The slot portion 4'' lies within the region in which the portion 24 intersects the member 3 when the implement is open (Figure 1). The members 2 and 3 and the strip 5 are formed in one piece from synthetic resin, in particular by a single mould. The greater width of the portion 4'' enables the mould elements required to form the slot 4 and to separate the two members 2 and 3 to be inserted at the moulding stage. When in use, the two members 2 and 3 are rotated relatively about the intermediate portion of the strip 5, which flexes to hence define a sort of hinge; the strip 5 is made conveniently thin to enable it to flex. When the implement clamps an object between its portions 21 and 32, the action of the hand on the eyelets 22 and 32 subjects the strip to a traction force, the strip 5 consequently being able to conveniently withstand this force even if thin. On the eyelets 22 and 32 there are provided two tabs 25 and 35 with toothing 27 which, when the implement is in its closed position, mutually engage to maintain the implement in its closed position. Numerous modifications of a practical and applicational nature can be made to the invention, but without leaving the scope of the claims as claimed hereinafter.

Claims: A manual implement of synthetic resin, such as forceps for medical use, comprising two members (2, 3) which intersect in an intermediate region and are arranged to rotate one relative to the other; of said members (2, 3) that portion (21, 31) which acts on objects being positioned at one of their ends, and that portion (22, 32) which is operated by the hand being positioned at the other end, a flexible strip (5) being provided joining together the two members (2, 3) to define the hinge constraint between the two members (2, 3), and said two members (2, 3) and said strip (5) being formed in one piece from synthetic resin, characterised in that: a first said (2) passes through a through slot (4) provided within the thickness of the second said member (3), said slot (4) defining within second member (3) two spaced-apart walls (33) which embrace the first member (2), said slot (4) having a length such as to enable the two members (2,3) to rotate relative to each other. A implement as claimed in claim 1, characterised in that said strip (5) is in an intermediate position between the portions (21, 31) which act on objects and the region of mutual intersection of the two members (2, 3). A implement as claimed in claim 2, characterised in that said slot (4) has a portion (4') of width substantially equal to the thickness of that portion (24) of the first member (2) which moves within the slot (4), said portion (4') of the slot (4) and said portion (24) of the first member (2) being mutually engaged under conditions of sliding contact when the implement is closed. A implement as claimed in claim 3, characterised in that said slot (4) comprises, within the region in which the first and second members (2, 3) intersect when the implement is opened, a second portion (4'') of width substantially greater than the thickness of said portion (24) of the first member (2).

Inventors: PARMIGIANI CORRADO, PARMIGIANI, CORRADO
Applicants: CGM SPA, C.G.M. S.P.A.
Application year: 1994
Main classification: A61B17
IPC codes: A61B17